blob: 373b701d9c6feac53635593f5a9db1a238e5944b [file] [log] [blame] [edit]
/* $OpenBSD: setenv.c,v 1.13 2010/08/23 22:31:50 millert Exp $ */
/*
* Copyright (c) 1987 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/* OPENBSD ORIGINAL: lib/libc/stdlib/setenv.c */
#include "includes.h"
#if !defined(HAVE_SETENV) || !defined(HAVE_UNSETENV)
#include <errno.h>
#include <stdlib.h>
#include <string.h>
extern char **environ;
static char **lastenv; /* last value of environ */
/* OpenSSH Portable: __findenv is from getenv.c rev 1.8, made static */
/*
* __findenv --
* Returns pointer to value associated with name, if any, else NULL.
* Starts searching within the environmental array at offset.
* Sets offset to be the offset of the name/value combination in the
* environmental array, for use by putenv(3), setenv(3) and unsetenv(3).
* Explicitly removes '=' in argument name.
*
* This routine *should* be a static; don't use it.
*/
static char *
__findenv(const char *name, int len, int *offset)
{
extern char **environ;
int i;
const char *np;
char **p, *cp;
if (name == NULL || environ == NULL)
return (NULL);
for (p = environ + *offset; (cp = *p) != NULL; ++p) {
for (np = name, i = len; i && *cp; i--)
if (*cp++ != *np++)
break;
if (i == 0 && *cp++ == '=') {
*offset = p - environ;
return (cp);
}
}
return (NULL);
}
#if 0 /* nothing uses putenv */
/*
* putenv --
* Add a name=value string directly to the environmental, replacing
* any current value.
*/
int
putenv(char *str)
{
char **P, *cp;
size_t cnt;
int offset = 0;
for (cp = str; *cp && *cp != '='; ++cp)
;
if (*cp != '=') {
errno = EINVAL;
return (-1); /* missing `=' in string */
}
if (__findenv(str, (int)(cp - str), &offset) != NULL) {
environ[offset++] = str;
/* could be set multiple times */
while (__findenv(str, (int)(cp - str), &offset)) {
for (P = &environ[offset];; ++P)
if (!(*P = *(P + 1)))
break;
}
return (0);
}
/* create new slot for string */
for (P = environ; *P != NULL; P++)
;
cnt = P - environ;
P = (char **)realloc(lastenv, sizeof(char *) * (cnt + 2));
if (!P)
return (-1);
if (lastenv != environ)
memcpy(P, environ, cnt * sizeof(char *));
lastenv = environ = P;
environ[cnt] = str;
environ[cnt + 1] = NULL;
return (0);
}
#endif
#ifndef HAVE_SETENV
/*
* setenv --
* Set the value of the environmental variable "name" to be
* "value". If rewrite is set, replace any current value.
*/
int
setenv(const char *name, const char *value, int rewrite)
{
char *C, **P;
const char *np;
int l_value, offset = 0;
for (np = name; *np && *np != '='; ++np)
;
#ifdef notyet
if (*np) {
errno = EINVAL;
return (-1); /* has `=' in name */
}
#endif
l_value = strlen(value);
if ((C = __findenv(name, (int)(np - name), &offset)) != NULL) {
int tmpoff = offset + 1;
if (!rewrite)
return (0);
#if 0 /* XXX - existing entry may not be writable */
if (strlen(C) >= l_value) { /* old larger; copy over */
while ((*C++ = *value++))
;
return (0);
}
#endif
/* could be set multiple times */
while (__findenv(name, (int)(np - name), &tmpoff)) {
for (P = &environ[tmpoff];; ++P)
if (!(*P = *(P + 1)))
break;
}
} else { /* create new slot */
size_t cnt;
for (P = environ; *P != NULL; P++)
;
cnt = P - environ;
P = (char **)realloc(lastenv, sizeof(char *) * (cnt + 2));
if (!P)
return (-1);
if (lastenv != environ)
memcpy(P, environ, cnt * sizeof(char *));
lastenv = environ = P;
offset = cnt;
environ[cnt + 1] = NULL;
}
if (!(environ[offset] = /* name + `=' + value */
malloc((size_t)((int)(np - name) + l_value + 2))))
return (-1);
for (C = environ[offset]; (*C = *name++) && *C != '='; ++C)
;
for (*C++ = '='; (*C++ = *value++); )
;
return (0);
}
#endif /* HAVE_SETENV */
#ifndef HAVE_UNSETENV
/*
* unsetenv(name) --
* Delete environmental variable "name".
*/
int
unsetenv(const char *name)
{
char **P;
const char *np;
int offset = 0;
if (!name || !*name) {
errno = EINVAL;
return (-1);
}
for (np = name; *np && *np != '='; ++np)
;
if (*np) {
errno = EINVAL;
return (-1); /* has `=' in name */
}
/* could be set multiple times */
while (__findenv(name, (int)(np - name), &offset)) {
for (P = &environ[offset];; ++P)
if (!(*P = *(P + 1)))
break;
}
return (0);
}
#endif /* HAVE_UNSETENV */
#endif /* !defined(HAVE_SETENV) || !defined(HAVE_UNSETENV) */